Electroluminescent color lamp



Jan. 6, 1959 A, M H ]'N 2,867,739

I ELECTROLUMINESCENT COLOR LAMP Filed Jan. 5, 1956 FIG. 3

A e- CPS 0F 20 PULSED STEPS EACH B us one PULSED STEPS EACH United States Patent ELECTROLUMINESCENT COLOR LAMP Hyman A. Michlin, New York, N. Y.

Application January 5, 1956, Serial No. 557,562 Claims. (Cl. 313108) This invention relates to the art of electric lamps, and in particular to a wholly electric means for producing a light image in rapid changing resultant color values.

Hitherto the means for varying the image color of an electric sign was mechanically achieved by projecting color rays thereon, by properly placing color filters thereon, selectively controlling color picture elements and etc.

One object of this invention is to'provide a new and useful result in a means capable of rapidly varying or abruptly changing and effecting a wide variation in the emitted color of a color advertisement lamp.

Another object is to provide an advertising color lamp capable of varying and efiecting a wide variation of color without working parts and without the need for maintenance.

Another object is to provide an advertising color lamp adaptable'for mass production.

Another object is to provide an electroluminescent color lamp for advertising, producing attractive effects, color images and etc.

This application is a continuation-in-part of application Serial No. 220,173 filed April 10, 1951 now Pat. No.

The invention will be more readily understood by referring to the following description, taken in connection with the accompanying drawings, in which:

Figure l is a schematic illustration of a rapid color changing electroluminescent lamp for advertising.

Figure 1-A is a schematic cross-sectional perspective view of the electroluminescent lamp schematically illustrated in Figure 1.

Figure 2 is a schematic perspective View of a modification of the rapid color changing electroluminescent lamp.

Figure 3 is a graphic presentation of the relative potentials and their variations used to produce the rapid color changes of the electroluminescentcolor lamp.

Referring to Figures 1 and 1-A as a preferred embodiment and by way of example, the layer of transparent conductance 1 can be of glass made conductive by a layer of aluminum vaporized thereon. Transparent conductances are known in the art of which examples are Corning E-C glass which is on the market, and the Piper Patent No. 2,698,915 discloses another. The image layers of transparent conductance 16 and 17 can be made of a highly resistive glass base 2 having an image, in this case letter, placed in registry on the both sides of the glass and a film of aluminum evaporized thereon, so that on removing the letters there would be found two layers of transparent conductance 16 and 17 having letters 15. in highly resistive background. The transparent image conductance layers 16 and 17 can be a single layer of transparent image conductance instead of a glass support separating the layers 16 and 17. The layers of image conductance 16 and 17 can be formed by photographic processes wherein a photographic positive image in silver in gelatin can be placed on highly resistive glass and the gelatin dissolved. Other methods to efiect an image in conductance are known and very readily adaptable by those skilled in the art. The layer of opaque conductance 5 can be of silver supported on a solid insulative layer so that a reflective surface can be obtained for more efficient color light emission in one direction. Each electroluminescent phosphor layer 3 and 4 emit in a different color. Emission colors of electroluminescent phosphors are known to vary by varying the frequencies of the electric field applied. Illuminating Engineering, vol. 45, page 692 discloses that electroluminescent phosphors can be made to vary in color emission on application of electric fields varying from 60 C. P. S. to 3,000 C. P. S. The electroluminescent layers can be made thin or of such characteristics as to transmit light, and where desired it can be made thick or of such dielectric or density of opaque phosphors as to be opaque to light. The electroluminescent phosphors of the preferred embodiment are embedded in dielectric to form layers and having A. C. electric fields applied thereto so as to excite same to luminescence. This is not intended to be restrictive as D. C. electroluminescent phosphors, examples of which can be found in Physical Review, vol. 87, page 151; Piper Patent No. 2,698,915 and in the latter of which the phosphors zinc sulphide activated by copper, manganese, aluminum or silver are each known to emit light rays in different wavebands. It is known that phosphors can be made to change their emission characteristics by their method of preparation. Examples of electroluminescent phosphors suspended in castor oil (although glass can be used as the dielectric instead of castor oil, and other dielectric materials are used) to form layers which can be used in this preferred embodiment are described in the Journal of the Electrochemical Society, vol. 1C0, pzge 566 where A. C. electric fieldstrorn v. to 700 v. at from 60 C. P. S. to more-than 1000 C. P. S. were applied to produce electroluminescence; and of which the electroluminescent phosphor layer 3 can use the electroluminescent phosphor zinc sulphide copper with a trace amount of lead to emit blue to green, and by adding manganese to said electroluminescent phosphor the color emitted therefrom can be extended to yellow to deep orange which phosphors can be used in the electroluminescent phosphor layer 4. No exact color emission from each electroluminescent phosphor layer 3' and 4 is a requirement as only contrast or different color emission characteristics to form .difierent resultant color images is the essential. The whole'of theelectroluminescent color lamp, although not illustrated,-can be encased in glass for protection of the elements therein and for greater structural stability with the conductive wires 8,, 9, 10 and 11 extended therethrough. The electroluminescent phosphor layer 3 can be made opaque by the substances forming the phosphor layer or by forming a thick phosphor layer. 1

The source of A. C. electric energy can be of 244 C. P. S. which isVaried in abrupt steps in reduced and raised potentials of 60 v. each in 122 pulses of two C. P. S. each apportioned over 6 and fl cycles as is graphically illustrated in A of Figure 3. The source of A. C. electric energy 7 can boot C. P. S. which can be varied in abrupt steps in reduced and raised potentials of 60 v. each in'20' pulses of 6 C. P. S. each apportioned over one cycle as is graphically illustrated in B of Figure 3. So that on comparison of A and B of Figure 3 with A starting at the highest potential step and B starting at its lowest potential step there would result, as is graphically illustrated, that at the end of a one second cycle that A would be two steps of potential ahead of its starting potential step in one second of cycles so that it would take ten seconds to be at its original position relative to B so that there is a complete change in variation of colors every ten seconds.

This is by way of example as the cycles can be varied to produce a lesser or greater rapidity of color changes.

Figure 2 schematically illustrates another modification of an electroluminescent .color lamp 13 wherein there are two assemblies of electroluminescent phosphors .each emitting in different colors. In one assemblythe elecroluminescent phosphor layer 4 emits light rays in two colors one color of which is emitted for the lettering 19 and the other emitted color for the background, which layer is sandwiched between two transparent layers of conductance 1. In the other assembly the electroluminescent phosphor layer 3 emits in a different color for the letters and a different color for the background than emitted by like parts of the electroluminescent phosphor layer 4; and which is sandwiched between the transparent layer of conductance 1 and the opaque layer of conductance 5 backed on a solid insulative substance. Both assemblies are'superimposed relativegto each other and separated by a layer of transparent insulation 12. A layer of supporting substance 18 can be of metal. The applying of electric fields in changed values in accordance with time will produce a color image in a different color background and with rapid changes as to resultant colors. 1 Referring to Figures 1 and l-A to describe a system of operation, negative potential from source 6 is transmitted through conductances 8.to image layer of conductance 16 and positive potential from source 6 is transmitted through conductance 9 to opaque layer of conductance 5 so as to form an image in blue to green in changed intensities. Negative potential from source 7 is transmitted through conductance 11 to image layer of conductance 17 and positive potential from source 7 is transmitted through conductance to layer of transparent conductance 1 so as to form an image in yellow to deep orange in rapidly.changed intensities. Precision color emission is not essential as color emission for producing resultant colors are of the essence. So that by reason of the different time intervals and synchronizations of the different pulses and cycles per second producing the changed'intensities of the different emitted Li colors from each of the electroluminescent phosphor layers 3 and 4, due to the different pulses and cycles per second of the different intensities of potentials transmitted to each of the electroluminescent phosphor layers 3 and 4, there is effected rapid resultant image and background color changes.

While the present invention has been described with reference to a particular embodiment and modifications thereof, it will be understood that numerous modifications y may be made by those skilled in the art without actually departing from the invention. Therefore, I aim in the appended claims to cover all such equivalent variations as come within the true spirit and scope of the foregoing disclosure. I claim:

1. The meansfor producing an electroluminescent pattern in rapidly changing resultant colors comprising a plurality of superimposed electroluminescent phosphor layers, each layer emitting in at-least one color, at least one area of each layer emitting in a color different from and in superimposed relation with an area of a color in at least one other layer; means for simultaneously selectively energizing individual areas of the electroluminescent nhosphor layers to selectively effect different color emission in different intensities from the electroluminescent layers so as to produce a resultant color pattern; and means for varying the said selective energizing of color eniission so as to produce patterns in changing resultant co ors.

2. The means for producing an image in rapidly changing resultant colors comprising a plurality of superimposed electrically controlled color light emitting layers, each said layer emitting with at least one color in one layer differing in color emission from at least one other layer; means for simultaneously selectively energizing individual areas of the color emitting layers to selectively effect different color emission indifferent intensities from the color emitting layers so as to produce a resultant color pattern; and means for varying said selective energizing to produce a changing color selection and intensity of emission so as to produce an image in changing resultant colors by selective combining of the different colors emitted from each of the color emitting layers.

3. A color producing electroluminescent lamp capable of rapidly changing the resultant colors emitted therefrom comprising a plurality of electroluminescent phosphor layers arranged in superimposed relation .to, each other, each said electroluminescent layer emitting in a different color; means to separately apply an image in electric energy to each of said electroluminescent phosphor layers so as to produce rapid resultant color image changes.

4. The color producing electroluminescent lamp of claim 3 and electric energy source means of at least two different changing electrieenergy values ,to transmit a different changing electric energy value to said means to separately apply electric energy to each of said electroluminescent phosphor layers so ,as toproduce rapid resultant color image changes.

5. The electroluminescent color lamp-of claim 3 in which each of the electroluminescent phosphor layers are capable of emitting inat least-one color.

6. The electroluminescent color lamp of claim' 7 in which each of the electroluminescent phosphor layers are capable of emittingin at least one color.

7. A color producing electroluminescent lamp capable of rapidly changing the resultant colors emitted therefrom comprising a pluralityof electroluminescent phosphor layers arranged in superimposed relation .to each other, each said layer emitting in a different color; and conductances for separately applyingan image in electric energy to each electroluminescent phosphor layer on transmission of suitable electric energy thereto.

8. The electroluminescent phosphor color lamp of claim 7 in which the conductances are in an image of conductivity to thereby form and apply an image in electric energy to each electroluminescent phosphor layer.

9. The color producing electroluminescent lamp of claim 7 and electric energy source means of at least two different changing electric energy values to transmit a different chan ing electric ener y value to each of said conductances to separately apply electric energy to each of said electroluminescent phosphor layers so as to produce ranid resultant color image changes.

10. The color producing electroluminescent lamp of cla m 8 and electric energy source means of at least two different changing electric energy values to transmit a different chan ing electr c ener y value to each of said conductances to separately apply electric energy to each of said electroluminescent phosphor layers so as to produce rapidresultant color image changes.

References Cited in the file of this patent UNITED STATES PATENTS 

